This invention relates to safety barriers to prevent vehicles such as fork lifts from inadvertently driving off the end of truck or railroad loading docks.
Loading docks are typically found in many businesses and warehouses. A loading dock is usually a platform approximately four feet above ground level thereby permitting trucks to back up to the loading dock and to have a level surface on which to walk into the truck or to drive a fork lift onto the truck for loading or unloading purposes. Loading docks are usually open to the outside with a large vertically moveable door which is used to open and close access between the loading dock and the building. Interior to the door are guideposts which are located at either side of the door frame. The purpose of the guideposts is to prevent striking of the door frames by fork lifts while loading and unloading the trucks. These guideposts are typically circular in nature and approximately three to four feet in height. They are designed and constructed to withstand impacts from the fork lifts. While the door may be closed the majority of the time the loading dock is not in use, the doors may be opened for ventilation in warm weather, while trucks are being changed at the loading docks, or for other reasons.
Open doors on the loading docks present safety hazards. Personnel may inadvertently walk through the door and step off the edge of the dock or fork lifts, while maneuvering in the warehouse, may inadvertently back or drive out of the door. Limited visibility from the fork lift create a situation where it is difficult for the fork lift driver to discern the edge of the loading dock. Consequently, there is great risk of the fork lift being driven or backed off the edge of an empty loading dock. This situation has resulted in severe injuries to and even accidental death of the fork lift driver. Thus, it is desirable to install a safety barrier across the door to prevent such accidents from happening. For the barrier to be effective, it should be durable and strong enough to prevent a fork lift from breaking through and driving off the loading dock. The barrier should be easy to operate so that a minimal amount of time and effort is required to open and close the barrier. In the event of an impact with the barrier by a fork lift or similar vehicle, the barrier should sustain minimal damage so that it may be repaired quickly and inexpensively. The barrier should also incorporate a design to prevent blockage of the loading dock doorway so as not to hamper or interfere with the loading or unloading of trucks and the use of the loading dock. The barrier should also be able to be retrofitted into existing doorways utilizing current building structures on which to mount the barrier, thus minimizing the amount of building modifications necessary to incorporate the barrier.
It is an object of this invention to provide a safety barrier for use in existing warehouses which is readily attachable to the guideposts on either side of the loading dock doorway. The safety barrier mounts are attached to the guideposts in a horizontally rotatable fashion with a rigid barrier arm extending between the mounts. The barrier arm is pivotal at one end with the opposite free end raised for access to the loading dock and lowered into locking engagement with the other mount to block the vehicle passageway. It is a further object of this invention to incorporate a locking mechanism at the free end of the barrier arm such that when the free end of the barrier is engaged in the mount, that the barrier arm is retained by the mounts in the event a vehicle should impact the barrier. It is another object of this invention to provide a safety barrier which upon being impacted by a vehicle will result only in damage or deformation to the barrier arm and not to the remainder of the safety barrier, thus minimizing the number of parts required to be replaced to return the safety barrier to a functional status.